Nowadays, motors are widely being used as driving sources in every device. Size reduction of a device is desired for various devices. Specifically, for a device using a motor, a technology for achieving size reduction of the motor is proposed for size reduction of the device.
For example, in Patent Literature 1, to provide a technology for reducing a size of an electromechanical device, a technology in which the electromechanical device includes a central axis, a rotor magnet disposed along an outer periphery of the central axis, a rotor having an accommodation space that is open at least in one axial direction of the central axis between the central axis and the rotor magnet, a stator disposed at an outer periphery of the rotor, a revolution number converting mechanism disposed in the accommodation space and integrally configured with the rotor, a load connection unit disposed inside of the stator and configured to connect the revolution number converting mechanism and a rotational load, and a cross-roller bearing provided between the stator and the load connection unit is proposed.